The Internet of Things (IoT) is coming--actually, it is already here. You carry a mobile phone. Your mobile phone has sensors. Your mobile phone probably phones home and at least reports its location. The IoT is about interconnected devices that measure, report and manipulate themselves or their environment. Today, most interesting information is created by humans (Google searches, Facebook posts and comments, Twitter tweets). A lot of effort goes into analyzing this information, learning about users and tailor various services (or disservices such as ads and spam). But, as more and more devices become smarter and connected a lot more information will be collected from machines than humans. This information (that may include information about humans such as heart rate, body temperature and perspiration) will be an order of magnitude larger than the information we collect today. In addition, devices will be able to manipulate their environment, by collaborating without user intervention. This is all possible right now, however, it will be years if not decades until it becomes streamlined and invisible. Think smart cities, smart cars, smart appliances all connected and intelligently accomplishing goals. But, the challenges are enormous.
Today, it is relatively easy to hook up some sensors to a computer and start collecting data. But, the data is often meaningless. Without careful calibration and understanding the behavior of the sensors in different environments over time, the data coming out of them can be highly inaccurate and difficult to interpret. A lot of research is needed to understand these factors and a lot of this work has to be done whenever a new sensor model comes out and improves on previous generations.
Actuators modify their environment. The control problem and adaptation to their environment take a lot of dedicated work. General-purpose functionality is a very difficult problem even in narrow domains (see self driving cars).
Security, Safety and Privacy
This is another super tough problem. With ubiquitous sensing the powers that be may know pretty much everything about you. This information will be stored in huge databases that will eventually be compromised. Sensing devices will be hacked or communication will be intercepted. Encryption schemes will be broken or circumvented via back doors. Those are all prevalent issues with today's internet. What makes it even more critical with the IoT is that the surface area will be order of magnitudes greater, the amount and depth of information will be greater making it worthwhile to invest more effort in breaking and the ability of a hostile/rouge entity to take over physical infrastructure and devices.
But, there is no need to go as far as malicious entities. As Napoleon once said, "Don't attribute to malice that which can be attributed to incompetence." With so many new devices and software to manage them out there, plain bugs will have the potential to wreck havoc.
This is the other side of the coin. Assume the security, safety and privacy were solved to a reasonable degree. Now, we have a see of devices out there that need to communicate with each other and perform some useful actions. Establishing the protocols, integrations and trust relationships will be a huge undertaking. Heterogeneous devices will have to dynamically discover other devices in their environment, figure out how to work to together and do all that with minimal human involvement at scale.
The amount of data will be staggering. Already most companies drown in data and extracting real value out of it is a burning problem. The IoT will accelerate the rte of data collection. Automatic approaches for analysis and getting insights from all the data will need to be developed to contend this deluge of information.
Unlike software/apps/web sites -- we're talking about physical, tangible "things". They need power. They need connectivity. They need installation, maintenance or replacement. When your phone dies or when you want to upgrade you go to the store and buy a new one. When your house, office, car and city has millions if not billions of smart devices with short life times another approach is needed. The typical approach of a technician rushing to fix or replace a failed instrument will not scale to the IoT.
The challenges are enormous, but don't blink. The upside is too great. I see it happening on a small scale first. Various systems in narrow domains that will be expanded over time. Robots and drones will be utilized to maintain the physical substrate of installing, maintaining and replacing devices. The privacy, safety and security issues will require a lot of attention, but are at least global challenges and global solutions will be developed (as opposed to per device). The future is here. Enjoy the ride.